The Mutant Mouse Core will centralize effort and provide the expertise necessary to maintain stocks of mice with various mutations generated by gene targeting and/or transgene insertion for use by participating investigators. Investigators requiring mice with specific targeted mutations and/or transgenes will be able to obtain the appropriate genotypes in requisite numbers from the Core. The Core is thus responsible for the routine care of founder and breeding animals, the husbandry required to generate the experimental animals, their weaning, application of ear tags for identification, and obtaining genotypes for the relevant gene(s). The Core is also responsible for supplying suitable controls when they are not readily commercially available. Breeding programs will be carried out in coordination with each investigator to obtain the appropriate number of animals of the required genotypes. We will provide the investigators in the PPG renewal the following gene knockout mice; Angiotensin 1 receptor type l a floxed (ATIa-floxed) -/-, angiotensin II receptor type 2 (AT2) -/Y, endothelial nitric oxide synthase (Nos3 or eNOS) -/-, conditional knockouts of the a epithelial sodium channel (ENaC) in both the cortical collecting duct (CCD) alone and the CCD plus the connecting tubule (CNT), and cardiac myocyte specific knockout of the prostaglandin EP4 receptor (CS-EP4) -/-. We will provide the following transgenic mice: NF-KB/luciferase (NF-KB-LUC) Tg, and chicken ovalbumin specific a and p T-cell receptor (OT II) Tg mice. In addition the Core will provide mice, generated by homologous recombination, which have a gain-of-function in the PENaC gene as a mouse model of Liddle's syndrome. In addition the Core will provide the following strains, directly purchased as needed as experimental animals to PPG investigators; Ragl -/-, p47-/-, NZBWF1/J, and NZW/LacJ. RELEVANCE (See instructions): The Mutant Mouse Core of the PPG, Core C will provide genetically modified mice to support the investigations to be conducted in Projects l-IV, as described in those sections. Providing these core services will allow the investigators to concentrate on their experiments without having to concern themselves with the day-to-day husbandry and genotyping of mice.